​Autonomous Terrain-Mobility Performance Optimization: Fundamentals for Unmanned Ground Vehicles

​Assessment and control of autonomous mobility performance of unmanned ground vehicles (UGVs) should be based on a set of technical parameters that result directly from the interactive dynamics of wheels and terrain and should be measurable and controllable in real-time.

​It is important that the combination of those parameters should characterize the UGV technical productivity, and, thus, enable to assess and control UGV autonomous mobility performance. If such requirements are satisfied, the mobility optimization can facilitate autonomous, real-time control design and assessment of UGV mobility performance.

​The proposed wheel mobility performance index and the vehicle mobility performance (VMP) index mathematically relate the wheel circumferential forces and velocity characteristics to the theoretical maximum performance.

​The VMP-optimization is formulated as an examination for the optimal tire slippages. Essentially, their combination characterizes the best set of the wheel circumferential forces and the vehicle actual velocity for the maximum mobility performance.

​Computational results of mobility performance optimization for a 4x4 UGV simulated on homogeneous terrains and split terrains on flat surface and on slopes, with and without drawbar pull are discussed with application to a virtual driveline system that serves for fully electric vehicles with in-wheel motors. Some fundamentals are introduced for parameter estimation and model-less control.

​—Dr. Gorsich and Professor Vantsevich
Editors-in-Chief, Journal of Terramechanics

​Vladimir V. Vantsevich is a professor in the Department of Mechanical and Materials Engineering, Worcester Polytechnic Institute, Massachusetts. He serves as co-Director and Principal Investigator of the Autonomous Vehicle Mobility Institute (AVMI).

​David J. Gorsich, U.S. Army DEVCOM Ground Vehicle Systems Center, Warren, Michigan, was selected for a Scientific and Professional position in January 2009 and serves as the Army’s Chief Scientist for Ground Vehicle Systems. His research interests are vehicle design and mobility, system reliability, additive manufacturing, terramechanics, gaming engines and autonomy.